Error - unrecognized format character: 'M'

[mrquincle]

Octave 3.8.1, running testPmtk3:

error: __errplot__: unrecognized format character: 'M'
error: called from:
error:   /usr/share/octave/3.8.1/m/plot/util/__pltopt__.m at line 215, column 11
error:   /usr/share/octave/3.8.1/m/plot/util/__pltopt__.m at line 106, column 23
error:   /usr/share/octave/3.8.1/m/plot/draw/private/__errplot__.m at line 30, column 7
error:   /usr/share/octave/3.8.1/m/plot/draw/private/__errcomm__.m at line 52, column 25
error:   /usr/share/octave/3.8.1/m/plot/draw/errorbar.m at line 181, column 10
error:   /opt/pmtk3/demos/knnClassifyDemo.m at line 138, column 1
error:   /opt/pmtk3/testPmtk3.m at line 69, column 1